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PubMed1994

Retinal pathologic changes in multiple sclerosis.

PURPOSE: To describe the ocular pathologic changes in multiple sclerosis (MS), with attention to its effects on the uveal tract and retinal veins. METHODS: Cases of 26 patients with MS and 3 patients with neuromyelitis optica were reviewed; retinal trypsin digestion was performed on remaining wet tissue for 20 of these patients. Eyes were specifically examined for inflammation of the retinal vessels, uveal tract, retina, optic nerve, and pars plana. Specimens were also examined for atrophy of the optic nerve, ganglion cell, and nerve fiber layers. RESULTS: Atrophy of the nerve fiber and ganglion cell layers was present in 73% of the cases with MS and correlated with optic nerve atrophy; choroiditis was present in 11.5%; bilateral cyclitis without other foci of inflammation was present in 1 case; and retinal phlebitis was present in 20% (most of which were only identified after trypsin digestion). Optic nerve inflammation was present in two of the patients with neuromyelitis optica. CONCLUSION: Uveitis and retinal phlebitis are manifestations of MS. Trypsin digestion with microscopic examination is a sensitive method of testing for phlebitis, which may explain why the frequency found in this series is higher than in others. These lesions are similar to the perivenular cuffing that occurs in the central nervous system in MS.

Adult↗

PubMed1987

Retinal venous-venous anastomoses and capillary aneurysms in juvenile glaucoma.

Two patients with juvenile glaucoma, a 12-year-old boy and a 22-year-old woman, were noted to have venous-venous anastomoses and capillary aneurysms of the retina. Their intraocular pressures had exceeded the diastolic pressure of the central retinal artery for months. Accompanying the successful surgical reduction of the intraocular pressures, these changes in the retinal vessels promptly reverted or disappeared. We consider that these capillary aneurysms and venous-venous anastomoses are the sequelae of the prolonged elevation of the intraocular pressure.

Adult↗

PubMedDate not supplied

[Retinopathy of prematurity and immaturity . A clinical study].

The retinopathy of prematurity is the most important cause of blindness at children and one of the most frequent cause of blindness in the postnatal period. 435 newborn prematures and dismatures, were examined in the first two weeks since they were born. The ophthalmological exam showed vasoconstriction of retinal vessels. The treatment consisted in cryotHerapy with good results. The most up-to-date method is the therapy with argon laser mounted on the indirect ophthalmoscope.

Cryosurgery↗

PubMed1982

Acute rubella retinal pigment epitheliitis in an adult.

A 50-year-old man who had been taking betamethasone for 20 days experienced a slight bilateral decrease in visual acuity. There were localized dark-gray atrophic lesions at the posterior pole, accompanied by a diffuse detachment of the sensory retina. The retinal vessels appeared to be normal and only minimal anterior uveitis was present in the more severely affected eye. Fluorescein angiograms showed no masking of choroidal fluorescence in the early phase and late-phase fluorescein angiograms showed multifocal leakage of the dye into the subretinal space. Electro-oculographic findings were abnormal only during the acute stage in the more severely affected eye and returned to normal within three months. The retinal detachment spontaneously resolved within three months; visual acuity returned to normal but some atrophic areas remained in the retinal pigment epithelium. Because the antibody titer to rubella was 1:1,028 during the acute stage but decreased to 1:257 within one month, we believe this patient had rubella retinitis, a rare condition in adults. The betamethasone may have made him more susceptible to the viral infection.

Betamethasone↗

PubMed2005

The 'Sutured Skull' and intracranial bleeding in infants.

It is known that retinal haemorrhages can result in adults when elevated intrathoracic pressures due to coughing, cardiopulmonary resuscitation, etc., force blood into the head. In infants under one year of age retinal and intracranial haemorrhage commonly occur together, but the same is not true for the older child and adult. The role of the elasticity of the infant skull (resulting from suture and fontanelle stretching) compared to the rigid mature skull, was investigated in a computer aided method. This showed that although in the event of Valsalva-like situations very high lumen pressures may be present in both groups, in the rigid adult skull an immediate corresponding increase in intracranial pressure is produced which surrounds and supports vascular walls leaving transmural pressures little changed. No such support is provided in the eye, and retinal vessels may rupture. Within the skull there may be drastic effects on brain circulation, but since changes in vascular transmural pressure are minimal vessel distension is not induced. In the infant skull the sutures stretch as pressure rises. Since vascular volume is only about 5% of intracranial volume each 1% increase in skull volume permits a 20% increase in vascular volume. Quite small skull expansions will allow dangerous vascular distension and risk of wall damage. Until skull bones fuse, intra-cranial bleeding will be expected in the soft infant skull in any situation where retinal haemorrhage alone is known to occur in the adult or child.

Cerebrospinal Fluid Pressure↗

PubMed1997

Retinopathy induced in mice by targeted disruption of the rhodopsin gene.

Retinitis pigmentosa (RP) represents the most common mendelian degenerative retinopathy of man, involving death of rod photoreceptors, cone cell degeneration, retinal vessel attenuation and pigmentary deposits. The patient experiences night blindness, usually followed by progressive loss of visual field. Genetic linkage between an autosomal dominant RP locus and rhodopsin, the photoreactive pigment of the rod cells, led to the identification of mutations within the rhodopsin gene in both dominant and recessive forms of RP. To better understand the functional and structural role of rhodopsin in the normal retina and in the pathogenesis of retinal disease, we generated mice carrying a targeted disruption of the rhodopsin gene. Rho-/- mice do not elaborate rod outer segments, losing their photoreceptors over 3 months. There is no rod ERG response in 8-week-old animals. Rho+/- animals retain the majority of their photoreceptors although the inner and outer segments of these cells display some structural disorganization, the outer segments becoming shorter in older mice. These animals should provide a useful genetic background on which to express other mutant opsin transgenes, as well as a model to assess the therapeutic potential of re-introducing functional rhodopsin genes into degenerating retinal tissues.

Age Factors↗

PubMed1976

Peripheral visual field restriction in chloroquine retinopathy. Report of a case.

Chloroquine compounds are known to cause a retinopathy which typically begins in the central fundus giving rise to a "bull's eye" macula. Ultimately peripheral changes may become apparent. In the routine eye examination of such patients emphasis has been laid on the central area of the fundus. A case is presented where the retinopathy was not diagnosed until marked peripheral changes had occurred with peripheral pigment changes, attenuated retinal vessels, slight optic atrophy, peripheral visual field restriction and a subnormal electroretinogram. The typical "bull's eye" changes were not apparent. Routine examination of the peripheral fundus by means of ophthalmoscopy and perimetry is necessary to avoid missing any such retinopathy.

Adult↗

PubMed1994

Glutamate receptor antagonists protect against ischemia-induced retinal damage.

The effects of intravitreal injections of excitatory amino acid receptor antagonists have been studied on the ischemic neuronal damage induced by photochemical occlusion of the retinal vessels. Rats were systemically injected with rose bengal fluorescein dye and one of their eyes was exposed to bright light. The activities of the enzymes, choline-acetyltransferase and glutamate decarboxylase, were measured as an index of neuronal loss in the lesioned tissue. Lesioned retinas had a 75 +/- 5% reduction in choline-acetyltransferase activity and a 72 +/- 8% reduction in glutamate-decarboxylase activity, suggesting that the lesion causes a massive loss of retinal neurons, which use acetylcholine or gamma-aminobutyric acid (GABA) as neurotransmitter. A single intravitreal injection of excitatory amino acid receptor antagonists, performed immediately after the lesion, significantly reduced this loss. Both alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) and N-methyl-D-aspartate) (NMDA) types of ionotropic glutamate receptor antagonists were active in a dose-dependent manner. Almost complete protection was also obtained with relatively large doses of thiokynurenic acid (400 nmol), a non-selective antagonist of both AMPA and NMDA glutamate receptors, while 7-Cl-thiokynurenic acid, a potent and selective glycine receptor antagonist, was not active up to 200 nmol. These results strongly suggest that excitotoxic mechanisms are involved in ischemia-induced neuronal death in the retina and that appropriate treatments with antagonists of both AMPA and NMDA receptor types may significantly reduce this damage.

2-Amino-5-phosphonovalerate↗

PubMed2003

Lipopolysaccharide/interferon-gamma and not transforming growth factor beta inhibits retinal microglial migration from retinal explant.

BACKGROUND: /aims: The retina possesses a rich network of CD45(+) positive myeloid derived cells that both surround inner retinal vessels and lie within the retina (microglia). Microglia migrate and accumulate in response to neurodegeneration and inflammation. Although microglia express MHC class II, their role remains undefined. The aims of this study are to investigate changes in human microglia phenotype, migration, and activation status in response to pro-inflammatory and anti-inflammatory stimulation. METHODS: Donor eyes were obtained from the Bristol Eye Bank with consent and whole retina was removed. 5 mm retinal trephines were cultured in glucose enhanced RPMI on cell culture insert membranes for up to 72 hours. The effects of lipopolysaccharide/interferon-gamma (LPS/IFNgamma) and transforming growth factor beta inhibits (TGFbeta) stimulation, alone or in combination, on migration, phenotype, and activation status (iNOS expression) of microglia were studied using immunofluorescence and cytokine analysis by ELISA. RESULTS: CD45(+) MHC class II(+) retinal microglia were observed within retinal explants, and in culture microglia readily migrated, adhered to culture membrane, downregulated MHC class II expression, and produced interleukin 12 (IL-12) and tumour necrosis factor alpha (TNFalpha). Following LPS/IFNgamma stimulation microglia remained MHC class II(-) iNOS(-), and secreted IL-10. Migration was suppressed and this could be reversed by neutralising IL-10 activity. TGFbeta did not affect ability of microglia to migrate and was unable to reverse LPS/IFNgamma induced suppression. CONCLUSIONS: Microglia readily migrate from retinal explants and are subsequently MHC class II(-), iNOS(-), and generate IL-12. In response to LPS/IFNgamma microglia produce IL-10, which inhibits both their migration and activation. TGFbeta was unable to counter LPS/IFNgamma effects. The data infer that microglia respond coordinately, dependent upon initial cytokine stimulation, but paradoxically respond to classic myeloid activation signals.

Cell Adhesion↗

PubMed1991

Advanced Coats' disease.

Advanced Coats' disease and retinoblastoma can both present with the triad of a retinal detachment, the appearance of a subretinal mass, and dilated retinal vessels. Thus, even the most experienced observer may not be able to differentiate these entities on ophthalmoscopic findings alone. Coats' disease is the most common reason for which eyes are enucleated with the misdiagnosis of retinoblastoma. Ultrasonography is the auxiliary diagnostic test most easily incorporated into the clinical examination, and can be utilized repeatedly without biologic tissue hazard. Ultrasonically identifiable features allowing differentiation between Coats' disease and retinoblastoma include the topography and character of retinal detachment and presence or absence of subretinal calcifications. Ultrasonography is of lesser use in poorly calcified retinoblastoma and in detecting optic nerve or extraocular extension in heavily calcified retinoblastoma. CT is perhaps the single most valuable test because of its ability to: (a) delineate intraocular morphology, (b) quantify subretinal densities, (c) identify vascularities within the subretinal space through the use of contrast enhancement, and (d) detected associated orbital or intracranial abnormalities. Optimal computed tomographic studies, however, require multiple thin slices both before and after contrast introduction and expose the child to low levels of radiation if studies are repeated periodically. MR imaging is valuable for its multiplanar imaging capabilities, its superior contrast resolution, and its ability to provide insights into the biochemical structure and composition of tissues. It is limited in its ability to detect calcium, which is the mainstay of ultrasonic and CT differentiation. Aqueous LDH and isoenzyme levels were not valuable in distinguishing between Coats' disease and retinoblastoma. The value of aqueous NSE levels in the differentiation of advanced Coats' disease and exophytic retinoblastoma deserves further study. Specimens from patients with intraocular hemorrhage should be viewed cautiously, since erythrocytes contain high levels of enolase. Analysis of subretinal aspirates is an extremely accurate method of confirming the diagnosis of Coats' disease. The key diagnostic findings are the presence of cholesterol crystals and pigment-laden macrophages and the absence of tumor cells on fresh preparations. The technique should be reserved for patients where retinoblastoma has been ruled out by all noninvasive means and massive subretinal drainage is anticipated. The natural progression in advanced Coats' disease is toward the development of a blind, painful eye. Spontaneous regression does rarely occur, and some eyes quietly progress to a phthisical state.(ABSTRACT TRUNCATED AT 400 WORDS)

Child↗

PubMedDate not supplied

[Blood circulation in the conjunctival blood vessels of patients with diabetes mellitus].

The state of the microciculatory system of the eye cojunctiva was studied in 107 patients suffering from diabetes mellitus and in 30 practically healthy persons. 85% of diabetic patients displayed marked changes in the conjunctival hemodynamics with a deranged tone and structure of microvessels, increase in their permeability and resistance, and also in worstened blood rheological properties. Disturbances of the conjunctival microcirculation observed from the first years of diabetes mellitus onset reached the maximum in the moderately severe form of diabetes over 10 years in duration with intense diabetic microangiopathies. In comparing the results of a study of the conjunctival and retinal vessels, conjunctival microcirculation was found to be disturbed in 68% of patients with the normal ophthalmological picture of the optic fundus and in all patients with diabetic retinopathies. Microphotography of the conjuctival vessels is recommended in patients with diabetes mellitus for early diagnosis of microhemodynamic disturbances.

Adolescent↗

PubMed1977

[Findings on retinal surface by scanning electron microscopy. III. Epivascular glial clusters (author's transl)].

The findings by scanning and transmission electron microscopy of multiple glial excrescences from the retina into the cortical vitreous body are described. These formations are located in lines above superficial retinal vessels. The findings are compared with those from light microscopy of similar formations. The pathogenesis and the possible significance as retinovitreal attachments for rhegmatogenous defects of the retina and for posterior vitreous detachments are discussed.

Aged↗

PubMed2000

Optic disk pallor and retinal atrophy in Sotos syndrome (cerebral gigantism).

PURPOSE: To report a case of Sotos syndrome (cerebral gigantism) with megalophthalmos, optic disk pallor, and retinal atrophy. METHODS: Case report. RESULTS: A 22-year-old man was diagnosed with Sotos syndrome with optic atrophy. His corneal diameters were 13 mm horizontally, and his optic disks were pale. His retinal vessels were attenuate in diameter, and small white spots were found on the retina. The results of a Goldmann visual field test were normal. His visually evoked potential to flash stimuli showed extended latent times and normal amplitudes. Keratometry was 40.5 diopters (8.33 mm) in both eyes. The axial length was 25.9 mm in the right eye and 25.4 mm in the left eye. CONCLUSION: Sotos syndrome may be associated with optic disk pallor and retinal atrophy.

Abnormalities, Multiple↗

PubMed1995

Automated retinal robotic laser system.

Researchers at the University of Texas and the USAF Academy have worked toward the development of a retinal robotic laser system. The overall goal of this ongoing project is to precisely place and control the depth of laser lesions for the treatment of various retinal diseases such as diabetic retinopathy and retinal tears. Separate low speed prototype subsystems have been developed to control lesion depth using lesion reflectance feedback parameters and lesion placement using retinal vessels as tracking landmarks. Both subsystems have been successfully demonstrated in vivo on pigmented rabbits using an argon continuous wave laser. Recent efforts have concentrated on combining the two subsystems into a single prototype capable of simultaneously controlling both lesion depth and placement. We have designated this combined system CALOSOS for Computer Aided Laser Optics System for Ophthalmic Surgery. Following the dual-use concept, this system is being adapted for clinical use as a retinal treatment system as well as a research tool for military laser-tissue interaction studies.

Animals↗

PubMed1990

[Idiopathic macular preretinal membrane in the elderly].

Idiopathic macular preretinal membrane was diagnosed in 14 patients, 4 males and 10 females, with age ranging from 47-72 years (mean 59.1 yrs) and a follow-up period from 1 month to 9 years (mean 2 yrs). The initial visual acuity varied from 0.05-1.5. Ophthalmoscopy and fluorescein angiography demonstrated fundus glinting light reflex, retinal fold, macular whitish preretinal membrane, distortion of the retinal vessels, and occasional microaneurysms and lamellar macular hole. The etiology was unknown. Progress of the disease was slow. Vision deteriorated in only 2 cases, and in 11 cases it remained stable for years.

Aged↗

PubMed1986

Retinitis pigmentosa: immunohistochemical and biochemical studies of the retina.

Several immunohistochemical and biochemical characteristics of retinas from two patients with retinitis pigmentosa (RP) were examined. Histochemically, interphotoreceptor retinoid-binding protein (IRBP) was found in the interphotoreceptor space in small areas of preserved peripheral retina, although enzyme-linked immunosorbent assay suggested that little IRBP was present. Antibodies to glial fibrillary acidic protein and factor VIII-related antigen corroborated retinal gliosis and retinal vessel attenuation, respectively, in the RP cases. Fibronectin showed similar staining in normal and affected tissue.

Aged↗

PubMed1990

[The efficacy of treating patients with intraocular hemorrhages with emoxypin].

Emoxipin, a home-made preparation approved by the Pharmacological Committee for clinical usage in 1986, is a retinal protector. Its usage is indicated for treatment of chorioretinitis, diabetic retinopathy, thrombosis of retinal vessels as well as to protects the retina from a damaging action of light of high intensity. In order to study therapeutic effectiveness of emoxipin in intraocular hemorrhages of different genesis, the preparation was used subconjunctivally, 0.5 ml of a 1% solution daily for 10-15 days. Emoxipin was used in 29 patients (29 eyes) with intraocular hemorrhages, of them, due to contusion of the eye--in 19, hypertonic disease--in 6, thrombosis of the central retinal vein--in 2, after intraocular operations--in 2 patients. As a result of the treatment, partial or almost total resolution of hemorrhages and a rise of visual acuity of different degree were recorded in all patients. Before treatment, visual acuity was from light perception to 0.04 in 26 eyes, from 0.09 to 0.3 in 3 eyes. After treatment, it rose to 0.1-0.2 in 12 eyes, to 0.3-1.0--in 17 eyes.

Adolescent↗

PubMed1984

[Clinical picture of an embolism of the central retinal artery caused by cholesterol crystals].

On the basis of six relevant personal observations the ophthalmoscopic signs of an embolism in the retinal vessels caused by cholesterol crystals are described. In the fundus characteristic red and yellow iridescent light reflexes from the crystals and muff formation around the afflicted vessels can be observed. Fluorescence angiography illustrates the grade of impediment to the blood-circulation. Embolism caused by cholesterol crystals in the retina is a bad prognostic sign with respect to the patient's life.

Aged↗